It is highly desirable, in a tremolo apparatus for an electric guitar, to have not only fine tuning but also individual string-height adjustment. Furthermore, it is important to achieve these and other results with a tremolo that is so flat on the upper side thereof, regardless of the positions of the fine-tuning elements, that the musician may, when he wishes, rest his hand or forearm on the tremolo. This is particularly true when the tremolo is one having a removable arm and which is capable of being locked during periods when no tremolo operation is desired.
The tremolo must be such that the various strings will remain on the intonation points even when the tremolo plate is pivoted or tilted upwardly to an extreme position. Otherwise, the tuning of the instrument would be lost during such intervals of extreme tilt-up.
Because of the frequent tendency of guitarists to bend strings in order to achieve sounds somewhat like those generated by a pedal guitar, it is important tht such bending produce little or no effect in the strings not bent. In other words, there should be little or no cross talk between the strings, even when very strong bending operations are occurring.
An additional factor, that has been recognized since tremolos for electric guitars were originated, is that the tremolo must return to its initial or "zero" position after the musician releases the tremolo arm. For this to occur, friction in the tremolo apparatus must be reduced to the lowest-possible amount commensurate with ruggedness and mass-producibility.